Virgin don't install by postcode, except as a rough guide to where they might be available. They are not required to connect to every premise in that postcode and will only do so if it is economic, so there is no guarantee that you can get it installed. Thay might however connect to the next houses outside that postcode, again if it's worth the cost. Ofcom won't know that fine detail.
If enough of your neighbours also express an active interest in joining Virgin Media by also filling in the cable my street form, we'll certainly review it and investigate as to whether it's viable to supply with our services.